In earlier versions of Warframe, Equipment, such as Warframes, rifle, pistol and melee weapons, would increase in level by gaining affinity through regular usage, in game pickups, and Login Rewards. Increasing an equipment level rewards a mod power point, which can be used to install mods on the equipment. See mods for more details.
A Warframe upgrade tree consists of 45 upgrade nodes but only 30 can be used. The nodes form a link between each other, and some nodes connect directly with the root node. An upgrade node cannot be taken if the preceding node has not establish connection with the root node. Warframes have 45 upgrade nodes in total, which are separated into two tiers; Normal and Supercharged. Normal tier consists a number (15) of upgrade nodes, while Supercharged tier consists of the rest of the upgrade nodes.
Each Weapon type equipment has 30 upgrade nodes in total, and are separated into two tiers; Normal and Supercharged. Normal tier consists of 15 upgrade nodes, while Supercharged tier consists of another 15 upgrade nodes.
Supercharged tier is locked by default when a frame or weapon is purchased with credits or crafted from the foundry, and requires either Orokin Reactor for Warframes or Orokin Catalyst for Weapons to unlock. Weapons and frames purchased with Platinum come with the Reactor/Catalyst already installed.
Upgrade points spent on any warframe or weapon can get a "RESPEC" which allows players to rearrange the points. This is esspecial useful for the frames as they have more slots than upgrade points available when fully leveled. Respec costs 2,000 Credits per upgrade point, for a total of 60,000 Credits for a fully leveled frame and will remove all mods currently attached.